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View Full Version : Software Fix for Headphones - What do you think of this?



earthmansurfer
06-16-2012, 07:19 AM
(I posted this on the boards with testers for the CTX - Hoping for a Minelab solution)

This is regarding Gray Ghost, Sun Ray, Chef Phones, etc. not shutting off the detectors speaker when connected to the headphone module. This is not about the WM10, just those of us with the starter pack.

What I did was first find the active pins - labeled 1, 2 & 3 in the photo below. Then I measured the Ohms between the active pins on the detached headphone module with the following setups:

1. Koss Headphones attached to headphone module (they work) - Pins 1 & 2 = 220 ohms, 1 & 3 = 113 ohms, 2 & 3 =111 ohms
2. Gray Ghost headphones with adapter attached (they work) ------ Pins 1 & 2 = 25ohms, 1 & 3 = 26 ohms, 2 & 3 - 0 ohms
3. Gray Ghost headphones with no adapter attached (don't work) - Pins 1 & 2 = open , 1 & 3 = 24 ohms, 2 & 3 = open
*Note - Chef Phones had same activity, but the ohms were higher at 46. I imagine Sun Ray would be similar.

So, I believe the software simply needs to listen between pins 2 & 3 and if there is an ohm reading, shut off the speaker.
With no headphones plugged in there is an open circuit between the pins, so there can be no accidental shutting off of the speaker.

This solution seems plausible. I would appreciate it if testers or those with connections to Minelab could please bring this to their attention for a software fix if I am indeed correct.

Thanks,
Albert

ps - Note the last picture with the adapter plugged in. It sticks out 2 and is a bit wobbly. My concern, as well as others, is if you come down on this in the field, you will break the headphone module.

midas
06-16-2012, 08:08 AM
What - a new problem with the CTX not accepting 3rd party headphones:huh:
I don't know if Minelab will address this concern. As it seems that the CTX design eliminates 3rd party accessories (coils, inline pinpointers, etc.) I love my X1 pinpointer and Killer Bee Headphones. I guess we will have to buy only Minelab accessories.

But, that is great diagnostic work, very plausible.

CyberSage
06-16-2012, 09:57 AM
As long as the Firmware has direct control over the switching function, this would probably work. I am speculating however that this is done by a custom circuit with a predefined setting at a module level. Probably would have to be done at a service center. I bet they fix this in future models. You could probably design an inline solution for now using parts from an electronics store..